Oil tank



April 17, 1928. v 1,666,661

J. N. PEW, JR

' on. TANK Filed June a. 1926 W/TA ESS:

f ing, which I Patented Apr. 17, 19%, Y i

UNITED mm J'OSEPH N. PEW,. 33., OF .ARDMOBE, PENNSYLVANIA, .LSSIGNOB TO SUIT OIL COM- max, on PHILADELPHIA, rnnnsnvimm, A coaroaanox or NEW JERSEY.

om rm.

Application filed June 8,

In tanks containing petroleum and its distillates, particularly gasolineand light crude oil, serious losses occur through breathis caused by the formation and condensation of gas. It is known t0--provide means that allow gas to breathe from the tank to a separate gas receiver in the day-time and back again into the tank at night; the gas receiver being separated from the tank and containing an'expansible and said means being built into an of the tank, but nearer collapsible breather bag. The object of my invention is to provide a new, improved and substantially diflt'erent means to guard against losses arising through breathing, forming part of the tank. .The accompanying drawin is a sectional clevational view of a tank em odying my invention in a preferred form. t

The tank comprises a bottom a, a cylindrical wall 6, internal steel columns 0, which preferably extend above the tank and which are located some distance from the center the center than the circumference; an annular roof d which closes the tank between the columns 0 and the wall I); and an inside vertically slidable or otherwise movable tank comprising a cylindrical wall 0 and a dome-shaped roof f and having an open bottom. The inside tank is counterweighted by suitable-means,

for example, by weights 9 connected to the roof of the inside tank by means of flexible connections 9 extending over pulleys 11 car-- ried by a frame-work formed by the upper parts of the columns 0 and by cross-beams 7'. The construction of wall 6 may be the same as that of an ordinary oil tank, as, for example. sections of iron, steel or concrete; welded 0r riveted together.

The 'roof at is formed in the shape of a flattened frustrum of a cone; that is, it slopes upward from the Wall 6 toward the inside tank at a small angle to the horizontal. The roof, near its inner edge, is preferably inclined at a relatively large angle to the horizontal. and depending from its inside edge is a flange 76, thereby forming in the main tank an annular gas pocket m surrounding the inside tank.

Extending from the gas pocket m are pipes n (hereinafter called a gas line) which extend er the tank and down outside the tank and hence under the tank' bottom, where they join a vertical pipe 9 extending -comprising a 1928. Bei-ial 30. 114,418.

up through the tank bottom and through the inside tank and terminating a short distance below the roof f of the inside tank.

The tank is also provided withan oil inlet .pipe p communicating with a swing pipe c-ally Within the tank, preferably within the inside tank, and terminating at the desired oil level in the tank; a water inlet pipe t; 'a water discharge pipe u communicatng with a swing pipe 1); a vacuum re-s lief w and a pressure relief valve :20; and a float 3 Extending from the-upper end of swing pipe 1- is a c0rd10, which extends over pulley 11 and around pulley 12 which is turned by means of a crank 13. Swing pipe 0 is operated by similar mechanism. loat 3 is used to operate controls which insure a definite level of liquid in the tank. These controls cause water to enter the tan as oil is pumped out and permit water to flow out as oi is pumped in. The controls need not be described, since they are well an oil discharge pipe 8 extending vertiknown in the art and form no part of the s flow into the space under tie the inside tank. Conversely any slight gas condensation relieves the pressure on the dome of the inside tank and allows it to descend. I

The tank will ordinarily be filled to the li quidlevel indicated int'the drawing. Gasoline may be drawn 011' by pumping water through pipe t into the bottom of the tank, the gasoline flowing out through the overflow pipe 8. The water is automatically discharged from the tank through .pipes u and 0 when gasoline is pumped in through pipes 12 and r. v Having now fully described my invention, what .I claim and desire to protect by Let-- ters Patent is a I v 1. .An oil tank com rising a roofed main container and an inslde floatin container roof and' an enc osing wall adapted to extend below the level of the oil in the main container, the floating conpart of the main container and the upper part of the inside container.

2. An oil tank comprising a relatively large roofed main container and a relatively small inside floating container comprising a roof and an enclosing wall adapted to extend below the level of the oil in the main container, thecontainers being arranged in'substantially concentric relationship and in free communication to allow flow of liquid between them, and means allowing flow of gas between the gas spaces of the containers, the inside container being movable to vary its gas capacity in accordance with variations in gas volume.

3. An oil tank comprising a relatively large main container and a relatively small inside container, the same being arranged in substantially concentric relationship, the

large container comprising an annular sl0p-' ing roof and coverin a that annular part of the main tank outside the inside container, the latter comprising an enclosing wall and a closed top and movable vertically in accordance with variations in gas volume, and means allowing flow of gas between the annular space under the higher part of the roof of the main container and the space under the closed top of the inside container. w

4. An oil tank comprising a relatively large main container and a relatively small inside container, the same being arranged .in substantially concentric relationship, the

large container comprising an annular sloping roof and covering that annular part of the main tank outside the inside con tainer, the latter comprising an enclosing wall and a closed top and movable verti-' cally In accordance with variations in gas volume, and a as pipe line extendin between the annu ar s ace under the higher part of the roof of t e main container and the space under the closed top of the inside container.

5. An oil tank comprising an outer wall and a roof, one section of which is movable verticall and another surrounding sectionof which is relatively fixed, the movable roof section carryinga depending cylindrical wall, and means allowing circulation of gas between the gas spaces under the two roof sections. c

6. An oil tank comprising a relatively large maincontainer and a relatively small inside container, the same being arranged in substantially concentric relationship, the large container comprising an annular roof sloping upward and inward at a relatively narrow angle to the horizontal throughout the greater portion of its width, that part thereof adjacent its inner edge and to the wall the inside container sloping inward and upward at a relatively wide angle to the horizontal and thereby forming an elevated annular pocket surrounding the inside container, the latter being movable to vary its gas capacity, and means allowing 

